Written by

Carole Feldman

The Associated Press

On the Web

It's a rite of fall — green leaves turn red and gold and then fall as trees prepare themselves for winter. It's an excellent time to give your trees a good once-over.

Are there dead branches or limbs, or large areas of fungus? Is the tree leaning? Are the roots well-grounded? A local arborist can determine whether there are problems that require immediate action.

Dead branches — or the entire tree — can come down in a storm. Be proactive, arborists say. "It's a lot cheaper to have the limb cut off than to fix your roof," said Jonathan Hammond, owner of Alpine Tree and Shrub Care in Denver.

And it's not just the dead limbs. "Pruning your tree can make it better able to withstand the extra weight of ice and snow," the Tree Care Industry Association says on its website Treecaretips.com. "Branches can be thinned to reduce their surface area and wind resistance."

The U.S. Forest Service has a guide for pruning trees, including dos and don'ts and when trees should be pruned.

But heights and chain saws can be a dangerous combination for amateurs. Sharon Lilly, director of education for the International Society of Arboriculture, said people should call a certified arborist for pruning large trees. "Homeowners can do the smaller and lower stuff themselves," she said.

There are other things that can be done to help trees withstand harsh winters.

Give them a "good, long, slow drink," Lilly said. All trees should get that fall watering, but especially young ones planted in the last three years, and evergreens.

A layer of organic mulch around the tree can help maintain moisture. The mulch also insulates and protects the upper roots, said Tchukki Andersen, staff arborist at the Tree Care Industry Association. And, it will help replenish nutrients in the soil. Think of it as an "early spring snack" for the trees when the area warms up, she said.

Arborists caution against placing mulch right up against the tree trunk. Think of shaping it like a saucer instead of a cone, said Vermont master gardener Ann Sherman: The mulched area should be as wide as possible to cover the underground roots but no deeper than 2 to 4 inches.

Fertilizing trees isn't necessary unless the soil is deficient in certain nutrients. Andersen said that if a tree is unhealthy, adding fertilizer will prompt it to put out new growth at the expense of its defense systems.

"Fertilizer is touted as a cure-all or a preventative," she said. "It's basically a substance that brings back a more natural balance of the soil."

For branches that have a weak union, or crotch, cabling is sometimes recommended. Lilly said that should be done by a professional, because there are "a lot of ways to do more harm than good."

A professional also can give you guidance on staking a tree to support it, Andersen said.

In areas where it snows a lot, small, fragile trees can be protected with a support teepee, essentially a tripod of plywood to prevent the snow from accumulating, she said. Also, some smaller trees can be winterized by temporarily tying some of the branches together.